I don't know the details on the subject; but my understanding is that the x50 should be able to do everything the Blackberry can and more; but only if you can get it connected to a network(wifi or maybe one of those bluetooth to cellphone arrangements). The blackberry uses the cellular data network for emails, so it can do its job pretty much anywhere you are likely to be, while, to the best of my knowledge, the x50 cannot talk to the cellular networks at all(except through a phone, as mentioned). So it really depends on your connectivity situation. Pockety PCs come with some flavour of Pocket outlook, and are plenty expandable in software terms, so they will beat the blackberry hands down when it comes to options; but if you cannot get connected to any networks, the person with the blackberry has an advantage.